diff --git a/grits/coarsegrain.py b/grits/coarsegrain.py
index 7d7fd2f..7c249e3 100644
--- a/grits/coarsegrain.py
+++ b/grits/coarsegrain.py
@@ -727,6 +727,8 @@ def save(self, cg_gsdfile, start=0, stop=None, stride=1):
                 new_snap = gsd.hoomd.Frame()
                 position = []
                 mass = []
+                #make an empty list for forces here
+
                 orientation = [] if self.aniso_beads else None
                 f_box = freud.Box.from_box(s.configuration.box)
                 unwrap_pos = f_box.unwrap(
@@ -738,6 +740,9 @@ def save(self, cg_gsdfile, start=0, stop=None, stride=1):
                     mass += [
                         sum(s.particles.mass[x]) * self.mass_scale for x in inds
                     ]
+
+                    #do the force calculation here
+                    
                     if self.aniso_beads:
                         for x in inds:
                             masses = s.particles.mass[x] * self.mass_scale